To form a conductive layer such as a semiconductor, metal and the like on a substrate, for example, the conductive layer may be formed by printing an ink layer on the substrate using an ink composite (conductive ink) in which conductive particles are dispersed, and sintering the conductive particles in the ink layer.
For example, the below described Patent Document 1 discloses a technique that coats an adhering layer by applying an adhesive to a substrate, coats a water repellent layer on the substrate on which the adhering layer is coated, prints conductive ink on the substrate on which the adhering layer and the water repellent layer are coated, and performs sintering of the printed conductive ink and curing of the adhering layer.
Further, the below described Patent Document 2 discloses a device that manufactures an electronic component by scattering metal microparticles on a substrate including an insulating pattern formed by a thermoset resin to adhere the metal microparticles on the insulating pattern, melting the insulating pattern by heating, fixing the metal microparticles on the insulating pattern, and removing the metal microparticles adhered to a surface of the substrate other than the insulating pattern.
In the method of Patent Document 1, a sintering condition is heating for 1 hour at 200° C. (paragraph 0044 of Patent Document 1), and in the method of Patent Document 2, a heating temperature of the insulating pattern is 150 to 200° C. (paragraph 0028 and the like of Patent Document 2), however, generally, upon heating a conductive pattern or an insulating pattern on a substrate, the heating is performed on an entire substrate; thus, the substrate that can be used is limited to those with high heat resistivity, such as substrates made of a thermoset resin with a high thermal resistance, for example, a BT resin including bismaleimide-triazine compounds and the like.
Due to this, as described in Patent Documents 3 to 5, there had been attempts to use an ink composite including nanoparticles, and form a metal pattern from the ink composite by photo irradiation. Methods that use light energy or microwaves in heating can selectively heat only the ink composite (nanoparticles), and there is a possibility that a resin having a lower thermal resistance than the above described resin can be used as the substrate.